RADIX: a minimal-resources rapid-access drilling system

Determining the expected age at a potential ice-core drilling site on a polar ice sheet generally depends on a combination of information from remote-sensing methods, estimates of current accumulation and modelling. This poses irreducible uncertainties in retrieving an undisturbed ice core of the desired age. Although recently perfected radar techniques will improve the picture of the ice sheet below future drilling sites, rapid prospective drillings could further increase the success of deep drilling projects. Here we design and explore a drilling system for a minimum-size rapid-access hole. The advantages of a small hole are the low demand for drilling fluid, low overall weight of the equipment, fast installing and de-installing and low costs. We show that, in theory, drilling of a 20mm hole to a depth of 3000m is possible in ~4 days. First concepts have been realized and verified in the field. Both the drill cuttings and the hole itself can be used to characterize the properties of the ice sheet and its potential to provide a trustworthy palaeo-record. A candidate drilling site could be explored in ~2 weeks, which would enable the characterization of several sites in one summer season.

Preinterventional screening of the TAVI patient: how to choose the suitable patient and the best procedure.

Transcatheter aortic valve implantation (TAVI) is a novel therapy, which has transformed the management of inoperable patients presenting with symptomatic severe aortic stenosis (AS). It is also a proven and less invasive alternative therapeutic option for high-risk symptomatic patients presenting with severe AS who are otherwise eligible for surgical aortic valve replacement. Patient age is not strictly a limitation for TAVI but since this procedure is currently restricted to high-risk and inoperable patients, it follows that most patients selected for TAVI are at an advanced age. Patient frailty and co-morbidities need to be assessed and a clinical judgment made on whether the patient will gain a measureable improvement in their quality of life. Risk stratification has assumed a central role in selecting suitable patients and surgical risk algorithms have proven helpful in this regard. However, limitations exist with these risk models, which must be understood in the context of TAVI. When making final treatment decisions, it is essential that a collaborative multidisciplinary "heart team" be involved and this is stressed in the most recent guidelines of the European Society of Cardiology. Choosing the best procedure is contingent upon anatomical feasibility, and multimodality imaging has emerged as an integral component of the pre-interventional screening process in this regard. The transfemoral route is now considered the default approach although vascular complications remain a concern. A minimal vessel diameter of 6 mm is required for currently commercial available vascular introducer sheaths. Several alternative access routes are available to choose from when confronted with difficult iliofemoral anatomy such as severe peripheral vascular disease or diffuse circumferential vessel calcification. The degree of aortic valve leaflet and annular calcification also needs to be assessed as the latter is a risk factor for post-procedural paravalvular aortic regurgitation. The ultimate goal of patient selection is to achieve the highest procedural success rate while minimizing complications and to choose patients most likely to derive tangible benefit from this procedure.

Additional surgical procedure is a risk factor for surgical site infections after laparoscopic cholecystectomy

PURPOSE: Surgical site infections (SSI) are associated with increased costs and length of hospital stay, readmission rates, and mortality. The aim of this study was to identify risk factors for SSI in patients undergoing laparoscopic cholecystectomy. METHODS: Analysis of 35,432 laparoscopic cholecystectomies of a prospective multicenter database was performed. Risk factors for SSI were identified among demographic data, preoperative patients' history, and operative data using multivariate analysis. RESULTS: SSIs after laparoscopic cholecystectomy were seen in 0.8 % (n = 291) of the patients. Multivariate analysis identified the following parameters as risk factors for SSI: additional surgical procedure (odds ratio [OR] 4.0, 95 % confidence interval [CI] 2.2-7.5), age over 55 years (OR 2.4 [1.8-3.2]), conversion to open procedure (OR 2.6 [1.9-3.6]), postoperative hematoma (OR 1.9 [1.2-3.1]), duration of operation >60 min (OR 2.5 [1.7-3.6], cystic stump insufficiency (OR 12.5 [4.2-37.2]), gallbladder perforation (OR 6.2 [2.4-16.1]), gallbladder empyema (OR 1.7 [1.1-2.7]), and surgical revision (OR 15.7 [10.4-23.7]. SSIs were associated with a significantly prolonged hospital stay (p < 0.001), higher postoperative mortality (p < 0.001), and increased rate of surgical revision (p < 0.001). CONCLUSIONS: Additional surgical procedure was identified as a strong risk factor for SSI after laparoscopic cholecystectomy. Furthermore, operation time >60 min, age >55 years, conversion to open procedure, cystic stump insufficiency, postoperative hematoma, gallbladder perforation, gallbladder empyema, or surgical revision were identified as specific risk factors for SSI after laparoscopic cholecystectomy.

AIV procedure for a CHEOPS demonstration model

The CHaracterizing ExOPlanet Satellite (CHEOPS) is an ESA Small Mission whose launch is planned for the end of 2017. It is a Ritchey-Chretien telescope with a 320 mm aperture providing a FoV of 0.32 degrees, which will target nearby bright stars already known to host planets, and measure, through ultrahigh precision photometry, the radius of exo-planets, allowing to determine their composition. This paper will present the details of the AIV plan for a demonstration model of the CHEOPS Telescope with equivalent structure but different CTEs. Alignment procedures, needed GSEs and devised verification tests will be described and a path for the AIV of the flight model, which will take place at industries premises, will be sketched. © (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

The EPICA Dronning Maud Land deep drilling operation

We report on the EPICA Dronning Maud Land (East Antarctica) deep drilling operation. Starting with the scientific questions that led to the outline of the EPICA project, we introduce the setting of sister drillings at NorthGRIP and EPICA Dome C within the European ice-coring community. The progress of the drilling operation is described within the context of three parallel, deep-drilling operations, the problems that occurred and the solutions we developed. Modified procedures are described, such as the monitoring of penetration rate via cable weight rather than motor torque, and modifications to the system (e.g. closing the openings at the lower end of the outer barrel to reduce the risk of immersing the drill in highly concentrated chip suspension). Parameters of the drilling (e.g. core-break force, cutter pitch, chips balance, liquid level, core production rate and piece number) are discussed. We also review the operational mode, particularly in the context of achieved core length and piece length, which have to be optimized for drilling efficiency and core quality respectively. We conclude with recommendations addressing the design of the chip-collection openings and strictly limiting the cable-load drop with respect to the load at the start of the run.

Procedure for short-lived particle detection in the OPERA experiment and its application to charm decays

The OPERA experiment, designed to perform the first observation of νμ→ντ oscillations in appearance mode through the detection of the τ leptons produced in ντ charged current interactions, has collected data from 2008 to 2012. In the present paper, the procedure developed to detect τ particle decays, occurring over distances of the order of 1 mm from the neutrino interaction point, is described in detail. The results of its application to the search for charmed hadrons are then presented as a validation of the methods for ντ appearance detection.

Is hysterectomy nowadays an obsolete procedure?

After the general morbidity reduction at the beginning of the century and the routine use of prophylactic antibiotics, a hysterectomy was generously, sometimes to generously indicated in the middle of the 20th century. This might be one of the major reasons why the procedure got a bad reputation. Furthermore, in the last decade, several new treatments for benign uterine pathologies have been developed which can be proposed to the patients instead of performing a hysterectomy. Therefore, the question might be asked, if nowadays there are still some indications for a hysterectomy or if the procedure is obsolete.

Drilling into debris-rich basal ice at the bottom of the NEEM (Greenland) borehole

After the NEEM (Greenland) deep ice-core drilling was declared terminated with respect to developing stratigraphic climate reconstructions, efforts were turned toward collecting basal ice-sheet debris and, if possible, drilling into the bedrock itself. In 2010, several meters of banded debris-rich ice were obtained under normal ice-drilling operations with the NEEM version of the Hans Tausen (HT) drill, but further penetration was obstructed by a rock in the path of the drill head at 2537.36 m. During short campaigns in 2011 and 2012, attempts were made to penetrate further using various reinforced ice cutters mounted on the HT drill head, tailored to cut through rock. These had some success in penetrating coarse material, but produced severely damaged cutters. Additionally a 51 mm diameter diamond cutting tipped rock drill was adapted to fit the NEEM drill. With this device, several additional meters of core containing subglacial sediments, rocks and rock fragments were collected. With these tools 1.39 m of additional material were obtained during the 2011 field season, and 7.1 m during 2012. Subglacial water refreezing into the newly formed borehole hindered further penetration, and the bedrock interface was not reached before final closure of the NEEM Camp.

A pilot test of the new Swiss regulatory procedure for categorizing clinical trials by risk: A randomized controlled trial

BACKGROUND/AIMS Several countries are working to adapt clinical trial regulations to align the approval process to the level of risk for trial participants. The optimal framework to categorize clinical trials according to risk remains unclear, however. Switzerland is the first European country to adopt a risk-based categorization procedure in January 2014. We assessed how accurately and consistently clinical trials are categorized using two different approaches: an approach using criteria set forth in the new law (concept) or an intuitive approach (ad hoc). METHODS This was a randomized controlled trial with a method-comparison study nested in each arm. We used clinical trial protocols from eight Swiss ethics committees approved between 2010 and 2011. Protocols were randomly assigned to be categorized in one of three risk categories using the concept or the ad hoc approach. Each protocol was independently categorized by the trial's sponsor, a group of experts and the approving ethics committee. The primary outcome was the difference in categorization agreement between the expert group and sponsors across arms. Linear weighted kappa was used to quantify agreements, with the difference between kappas being the primary effect measure. RESULTS We included 142 of 231 protocols in the final analysis (concept = 78; ad hoc = 64). Raw agreement between the expert group and sponsors was 0.74 in the concept and 0.78 in the ad hoc arm. Chance-corrected agreement was higher in the ad hoc (kappa: 0.34 (95% confidence interval = 0.10-0.58)) than in the concept arm (0.27 (0.06-0.50)), but the difference was not significant (p = 0.67). LIMITATIONS The main limitation was the large number of protocols excluded from the analysis mostly because they did not fit with the clinical trial definition of the new law. CONCLUSION A structured risk categorization approach was not better than an ad hoc approach. Laws introducing risk-based approaches should provide guidelines, examples and templates to ensure correct application.

Reconstruction of in-situ porosity and porewater compositions of low-permeability crystalline rocks: Magnitude of artefacts induced by drilling and sample recovery

Geological site characterisation programmes typically rely on drill cores for direct information on subsurface rocks. However, porosity, transport properties and porewater composition measured on drill cores can deviate from in-situ values due to two main artefacts caused by drilling and sample recovery: (1) mechanical disruption that increases porosity and (2) contamination of the porewater by drilling fluid. We investigated the effect and magnitude of these perturbations on large drill core samples (12–20 cm long, 5 cmdiameter) of high-grade, granitic gneisses obtained from 350 to 600 m depth in a borehole on Olkiluoto Island (SW Finland). The drilling fluid was traced with sodium–iodide. By combining out-diffusion experiments, gravimetry, UV-microscopy and iodide mass balance calculations, we successfully quantified the magnitudes of the artefacts: 2–6% increase in porosity relative to the bulk connected porosity and 0.9 to 8.9 vol.% contamination by drilling fluid. The spatial distribution of the drilling-induced perturbations was revealed by numerical simulations of 2D diffusion matched to the experimental data. This showed that the rims of the samples have a mechanically disrupted zone 0.04 to 0.22 cm wide, characterised by faster transport properties compared to the undisturbed centre (1.8 to 7.7 times higher pore diffusion coefficient). Chemical contamination was shown to affect an even wider zone in all samples, ranging from 0.15 to 0.60 cm, inwhich iodide enrichmentwas up to 180 mg/kgwater, compared to 0.5 mg/kgwater in the uncontaminated centre. For all samples in the present case study, it turned out that the magnitude of the artefacts caused by drilling and sample recovery is so small that no correction is required for their effects. Therefore, the standard laboratory measurements of porosity, transport properties and porewater composition can be taken as valid in-situ estimates. However, it is clear that the magnitudes strongly depend on site- and drilling-specific factors and therefore our results cannot be transferred simply to other locations. We recommend the approach presented in this study as a route to obtain reliable values in future drilling campaigns aimed at characterising in-situ bedrock properties.

[Pilot Project: Improved Lung Deposition via a New Nasal Inhalation Procedure].

INTRODUCTION Inhaled drugs can only be effective if they reach the middle and small airways. This study introduces a system that combines a trans-nasal application of aerosols with noninvasive pressure support ventilation. METHODS In a pilot study, 7 COPD patients with GOLD stages II and III inhaled a radiolabeled marker dissolved in water via a trans-nasal route. The mean aerosol particle size was 5.5 µm. Each patient took part in two inhalation sessions that included two application methods and were at least 70 hours apart. During the first session ("passive method"), the patient inhaled the aerosol through an open tube system. The second session ("active method") included pressure support ventilation during the inhalation process. A gamma camera and planar scintigraphy was used to determine the distribution of aerosol particles in the patient's body and lung. RESULTS The pressure supported inhalation ("active method") results in an increased aerosol lung deposition compared to the passive method. Above all, we could demonstrate deposition in the lung periphery with relatively large aerosol particles (5.5 µm). DISCUSSION The results prove that the combination of trans-nasal inhalation with noninvasive pressure support ventilation leads to significantly increased particle deposition in the lung.

A Bootstrap-Regression Procedure to Capture Unit Specific Effects in Data Envelopment Analysis

The Data Envelopment Analysis (DEA) efficiency score obtained for an individual firm is a point estimate without any confidence interval around it. In recent years, researchers have resorted to bootstrapping in order to generate empirical distributions of efficiency scores. This procedure assumes that all firms have the same probability of getting an efficiency score from any specified interval within the [0,1] range. We propose a bootstrap procedure that empirically generates the conditional distribution of efficiency for each individual firm given systematic factors that influence its efficiency. Instead of resampling directly from the pooled DEA scores, we first regress these scores on a set of explanatory variables not included at the DEA stage and bootstrap the residuals from this regression. These pseudo-efficiency scores incorporate the systematic effects of unit-specific factors along with the contribution of the randomly drawn residual. Data from the U.S. airline industry are utilized in an empirical application.

A standard operation procedure and a pilot water testing for herbicides in northwest Harris County, Texas

Herbicides are used to control the growth of weeds along highways, power lines, and many other urban locations. Exposure to herbicides has been linked to adverse health outcomes. This study was initiated to pretest for the presence of herbicides in multiple water sources near intersections in a corridor in the Northwest Harris County (specifically in the Highway 6/FM 1960, North Freeway 45, US 290 and S 99 corridor). Roadside water and tap water samples were collected and analyzed for herbicides using the established Environmental Protection Agency (EPA) Method 515.4: "Determination of Chlorinated Acids in Drinking Water by Liquid-Liquid Micro-extraction, Derivatization, and Fast Gas Chromatography with Electron Capture Detection." A standard operating procedure (adapted from the US EPA Method 515.4) was developed for subsequent, larger studies of environmental fate of herbicides and non-occupational exposure risks. Preliminary testing of 16 water samples was performed to pretest the existence of trace herbicides; all concentrations that were greater than the minimum reporting limits of each analyte are reported with a 99 percent confidence. This study failed to find concentrations above the limits of detection of the method in any of the samples collected on June 15, 2008. However, this does not indicate that the waters around the NW Harris County are free of herbicides and metabolites. A larger and repeated sampling in the region would be necessary to make that claim. ^